Lifting-jack



(No Model.) v

L. E. 86 P. MURPHY.

LIFTING JACK.

No. 391,382. Patented 001;. 16, 1888.

Lz- T WITNESSES:

4 A TTORIVEY,

@NITED STATES PATENT OFFICE.

LAXVRENOE E. MURPHY AND PATRICK MURPHY, OF ST. PAUL, MINNESOTA.

LIFTING-JACK.

EZPECIFICATION forming part of Letters Patent No. 391,382, dated October 16, 1888.

Application filed May 8, 1888. Serial No. 273,177.

To all whom it may concern.-

Be it known that we, LAWRENCE E. Mun- PHY and PATRICK MURPHY, of St. Paul, in the county of Ramsey and State of Minnesota, have invented a new and Improved Lifting- Jack, of which the following is a full, clear, and exact description.

The object of our invention is to provide a liftingjack of light construction and having an increased extent of movement of theliftingbar for the movement of the operating lever or handle, and in which the working parts may be conveniently oiled; and the invention consists in the construction and combination of parts, as hereinafter described and claimed.

Reference is to be had to the accompanying drawings, forming a part of this specification, in which similar letters of reference indicate corresponding parts in all the figures.

Figure 1 represents a central vertical section of a jack embodying ourimprovement. Fig. 2 is a perspective view of the same; and Fig. 3 is a cross-section on the line a: :20, Fig. 1.

The body of the jack preferably consists of the two members A A, bolted or otherwise suitably secured together and which are socketed or otherwise fixed to a base, B, one of the members of the body being formed with a longitudinal recess, a, in which works the ratcheted lifting-bar O, that is provided with an outwardly-extending foot, 0, the base B being formed with a through-slot b for the passage therethrough of the lifting-bar C.

In the side walls of the vertical recess aare formed vertical guidegrooves a a, in which guide projections c c on the lifting-bar 0 travel, and the members A A are united and braced near the upper end by a cross-piece, a which also guides and braces the lifting-bar O, the cross-piece having a vertical recess for receiving the lifting-bar.

The lifting-block D is formed with a throughslot, d, which receives the lifting-bar O, and is formed at the side opposite the teeth of the said lifting-bar with a tooth or inwardly-projecting edge, (1, which engages one of the teeth of the lifting-bar when the said lifting-block is moved upward in response to the movement of the operating-lever E, which is pivoted above the said block, the connection of the lifting-block and operating-lever being established through the medium of a link, F. By

(No model.)

this arrangement it will be seen that a very long lift is given the lifting-bar by each single movement of the operating-lever, and the dis engagement of the lifting-block from the lifting-bar is assured upon relieving the force exerted on the operating-lever, the block falling by its own gravity.

The retaining-dogG is pivoted on the inside of one of the members A or A of the body, and is normally held in engagement with the teeth of the lifting-bar by a spring, H. The disengaging-lever I of the dog is pivoted adjaccnt to said dog and extends outward beyond the body of the jack for convenient operation, and beyond its fulcrum it is formed with a toe, t, which engages a lug, g, on the retainingdog in such a manner as to disengage the said dog from the lifting-bar upon the outer end of the said lever I being depressed.

The lifting-bar C may be allowed to drop entirely below the other operating parts of the jaclnwhereupon the said parts may be conveniently oiled.

In order that the retaining-dog may be retained in position and not be displaced by its spring upon the removal of the lifting-bar, a stop, J, is provided,against which the said retaining-dog is forced by its spring.

It will be seen that the jack above described may be constructed very light, its working parts are few and simple in construction, it may be oiled with convenience and dispatch, and the extent of movement of the lifting-bar in response to the movement of the operatinglever is increased, each of which advantages is a great desideratum in railroading, for which purpose our improved jack is specially designed.

A suitable handle, K, is provided on the jack for convenicncein moving the same from place to place.

Having thus described our invention, what we claim as new, and desire to secure by Letters Patent, is

1. The combination, in a lifting-jack and with the ratcheted lifting-bar thereof, of a lifting-block having a tooth or inwardly-projecting edge for engaging the teeth of the lifting-bar, an operating-lever, a link connecting the said lever and lifting-block, and a retaining-dog, substantially as shown and described.

2. In a lifting-jack, the combination, with the body of the jack and a ratcheted liftingbar fitted to slide therein, of a lifting-block through which the ratcheted-bar passes, said block provided with an inwardly-projecting tooth, an operating-lever, a link pivoted to said lever and block, a spring-pressed retaining-dog, and a lever for disengaging said dog, substantially as described.

3. In a lifting-jack, the combination, with the body, a ratcheted lifting-bar fitted to slide in the said body, and means for raising said lifting-bar, of the spring-pressed retainingdog G, provided with the lug g, and the lever I, pivoted to the body and provided with the toe i, engaging the lug of the said dog, substantially as herein shown and described.

LAWRENCE E. MURPHY. PATRICK MURPHY.

Witnesses:

F. KNAUFT, J. O. STEWART. 

